1,3-Oxazole Rotational Spectra and Semi-Experimental Structures for 30 Isotopologues

Over 3900 transitions for the ground vibrational state of 1,3-oxazole were measured from 43 to 750 GHz. Spectra for 30 oxazole isotopologues, including 21 observed for the first time, were used to determine semi-experimental equilibrium and substitution structures. The dataset, authored by Brian J. Esselman and last updated in April 2026, is shared under a CC-BY-NC-4.0 license.

Use Cases

• Calibrating quantum chemistry calculations based on high-precision spectroscopic constants.
• Supporting astronomical searches for oxazole by providing reference spectra across a wide frequency range.
• Developing improved methods for semi-experimental structure determination to address issues with near-oblate asymmetric tops.
• Benchmarking the accuracy of vibration–rotation interaction corrections in molecular modeling.

Strengths

• Includes over 3900 measured and assigned rotational transitions for the ground vibrational state.
• Covers a broad spectral range from 43 to 750 GHz, relevant for modern radio telescopes.
• Provides data for 30 isotopologues, enabling redundant structural determination with high reported precision (0.0001-0.0002 Å in bond distances).

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count is unknown, which may limit suitability assessment for specific analytical tasks.
• The 14.3 MB file size suggests a relatively small dataset, potentially limiting the scope of analysis.

Provenance

Source

figshare

Collection Method

Rotational spectra were measured, assigned, and least-squares fit to sextic centrifugally distorted-rotor Hamiltonians.

Freshness

Last updated 2026-04-25 01:43:31; freshness should be verified.